Refrigerating apparatus



Dec. 11,v 1928.

F. E. DENNISON REFRIGERATING APPARATUS Filed July 21, 19.26

.lllllllllllllll Patented Dec. 11, 1928.

ermee PATENT 'OFFlCB FRENCH E. DENNISON, OF BELOIT, VISCONSIN, ASSIGNOB T0 NATIONAL REFRIGERA- TION CORPORATION, OF BELOIT, VISCONSIN, A CORORATIN 0F DELA`WARE. v

REFRIGERATING APPARATUS.

Application filed July 21,

This invention relates to a refrigerating apparatus and more particularly to a refrigerating unit which may be used as a condenser or an evaporator.

One of the objects of the present invention is to provide a construction of a refrigerating device, such, for instance, as a condenser or evaporator unit in which the number. of square feet of conduction and radiation surfacel is increased to a maximum and at the same time the unit in itself is so y constructed as to occupy a minimum amount of cubical space.

A further object of the invention is to provide a refrigerating unit which is particularly adapted as an evaporator for use in connection with soda fountains in which the unit is mounted in a vertical position for maintaining practically uniform temperature from top to bottom.

A still further object of the invention is to provide a,a construction of a refrigerating unit in which the refrigerant passing through the same is so distributed throughout the' unit as to maintain a uniform temperature at all points of the unit.

A still further object of the invention is to provide an improved refrigerating unit in which the refrigerant is caused to be passed through relatively narrow channels which permit rapid evaporation to such an extent as to prevent flooding of the unit.

These and other objects are accomplished by providing a construction and arrangement of the various arts in the manner hereinafter describe Vand particularly pointed out in the appended claims.

Referring to the drawings,

Fig. 1 is a side elevational' view partly in secion of my improved refrigerating unit, an

Fig. 2 is a cross-sectional view taken on the line 2 2 in Fig. 1.

The invention illustrated and described in the present instance is an improvement on, or a specific application of the construction of my invention described and claimed in the copending application, Serial No. y120,355 filed July 3, 1926.

The present invention in addition to affording a maximum conduction in radiation surface to the refrigerant within the refrigerating unit, also provides the advan` tages of occupying a minimum cubical space "between 1926. serial No. 123,992.

as pointed out in my copending application above referred to. v

The present. invention is specifically directed to a refrigerating unit which is especially adapted for use in soda fountains or ice cream cabinets in which the cylindrical containers of the ice cream may be positioned within the unit and the unit by reason of its construction will maintain a uniform temperature from top to bottom.

lu illustrating one embodiment of my in- .vention for accomplishing these results, I have shown the same as comprising an outer tubular metallic or hollow casing 10 within which is mounted a snugly fitting tubular or hollow casing 11. The casings 10 and 11 are made of relatively thin metal and are of suflicieut length to accommodate the entire length 'of an ice cream can or container.

`'lhe inner cylinder casing member 11 is provided with a plurality of V shaped peripheral grooves or passages 12. The grooves 12, of which there are three in number, are unformly spaced from each other but on each convolution of the three orrooves the pitch is gradually increased so that 'the three grooves on the inner cylindrical member are spaced relatively further apart as the bottom of the refrigerating unit is approached, as clearly shown in F ig. l.

The preferred method of makin my refrigerating unit consists of takmg two metal tubular members, one of which is adapted to snugly lit within the other. The peripheral su rface of the inner tubular member may be grooved or cut on a lathe in a manner Well known, so as to form the passageways for the refrigerant. lVhen the grooves or passages are cut on the inner tubular member, it is then inserted within the outer tubular member, after which the adjacent ends of both members are soldered or Welded so as to completely seal the passages the members. Obviously other methods may be employed in constructing my improved form of refrigerating unit and still be within contemplation of my invention.

It will be' readily understood that as the refrigerant circulates through these peripheral passages in the casing member 11, that a gradually lesser amount of refrigerant is required to cool a greater volume of ice cream as it approaches the bottom of the unitl so that the temperature throughout the unit is substantially uniform from top to bottom, thereby maintaining the ice cream or other substance at auniform temperature throughout. r i

Formed on the upper end ofthe inner casing member ll and communicating with the three passages 12 is an annular peripheral recess 13 which forms a distribution chamber for vthe incoming refrigerant supe plied thereto by thesupply pipe 14 which in turn is connected with the expansion valve of therefrigerating apparatus.

The cylindrical casing members 10 and 1l have their opposite ends soldered or Welded together as shown at l5. The lower .ends of the peripheral grooves 12 communicate.. with and discharge the refrigerant into a peripheral recess 16 formed in thc lower end of the casingll adjacent the bottom thereof. 'lhis recess vor chamber 16 is connected by .a conduit 17 through which the refrigerant is discharged from the unit. g

In `the operation of the above Idescribed device the refrigerant passes from the expansion valve through the conduit 14 into the 'distribution recess or chamber 13 where `it is distributed through the peripheral grooves 12. As the liquid refrigerant is being circulated through the grooves 12 the absorption of heat becomes so rapid on account 'of the relatively large radiation surface in comparison with theV relatively small channels in the unit,that the liquid in a short timebecomes vaporized before reaching the lchannel or recess 16 in the bottom of the'unit.

On account of the groovesA l2 being gradually spaced apart a greater distance toward the bottom of the unit, it will be readily seen that the unit maintains a uniform tempera-` ture throughout or from top to bottom.

In illustrating one embodiment of my invention, I have shown the same as comprising tWo cylindrical casing members in making up my unit, but it will, of course, be understood that forms, other than that shown inthe drawings embodying my principle of operation, may be made and still be Within is passing through both devices.

With my present construction as above described, I increase the rate of transfer of heat from the storage casing to the inside of the expansion unit and thereby make the same more efficient as compared with the pipe expansion coil of large cross section now in use. In the pipe construction it is apparent that a large amount of expanding gas passes on through in the center of the pipe without coming in direct contact with the heat transfer surface; when the as contacting'with the inner surface of talle pipe has absorbed lits quota of heat, it not only forms a barrier to the cold gas Within it but rises in temperature andthereby reduces the temperature difference between the outside and inside of the pipe wall, thus reducing the speed of the transfer of heat and the eiiiclency of the expansion coil.

`Vhile inthe above specification I have dcscribed one embodiment which my invention may assume in practice, it will, of course, be understood that the same is capable of modiiication without departing from the spirit and scope of my invention as expressed in the followingl claims.

I claim:

l. The combination of a refrigerating unit adapted to be inserted in a closed circuit refrigerating system for 4changing the state of the refrigerant thereof comprising a double walled cylinder having a spiral passage fornied between the walls, the inner and outer walls of said passage heilig arranged so close that a maximum of conducting area is afforded by said walls in proportion to the volume of said passage, means for conducting refrigerant to said unit at one end of said passage in one state and means for conducting said refrigerant from 100 said unit atthe other end of said passage in another state.

2. A refrigerating unit comprising a casing having a spiral passage formed therein, said passage having a varying pitch.

8. A refrigerating unit having a chamber formed therein comprising a plurality of spirally arranged passages of varying pitch.

4. A refrigeratincr unit comprising a casing having a chamber formed therein, said l 10 chamber'comprising a plurality of uniformly spaced spiral passages ofgradually varying pitch whereby said refrigerant is un-y equally distributed over said unit for maintaining the unit at a uniform temperature 115 throughout.

5. A- refri-gerating unit comprisiner an outercylindrical casing, an inner cylindmcal casing snugly fitting said outer cylindrical casing, there being a passage formed on said 12u inner cylindrical casing, of such a shape with respect to the longitudinal axis of the unit that a refrigerant passing through said passage unequall distributes said refrigerant for maintaining a` uniform temperature 125 throughout said unit.

6. A refrigerating unit comprising a eylindrical casing. an inner cylindrical casing snugly fitting said outer1casing,nthere being a spirally arranged passage formed in said x30 7 A refrigerating .unit comprising a cylin-' drical outer casing and a cylindrical inner casing snugly fitting said outer casing, a plurality of uniformly spacedQapart passages of progressively varying pitch formed between said casings for unequally` distributing the refrigerant passing therethrough whereby said unit is maintained at a -uniform temperature throughout. i

8. A refrgerating "unit 'comprising an i outer tubular casing and an inner tubular casing, there being aplurality of spirally arranged passages in said inner tubular casing, said passages arranged on said inner cylindrical casing in an uniformly increasing pitch as said passages approach the bottom of said unit whereby the refrigerant is unequally distribntedover the area of said unit for maintaining a uniform temperature throughout the unit.

9. A refrigeratinfr unit comprising afcasf" ing, a plurality oi'P spirally arranged Ipassages of gradually increasing pitch forming a chamber in said casing, an annular recess formed in the upper end of said casing and communicating with said passages for distributing the refrigerant in said passages,

unit

and a recess formed at the bottom of said casing for receiving :the refrigerant from said passages- 10. A refrigerating unit comprising a tubular outer casing, an inner tubular casing snugly fitting said outer casing, there being a plurality of spaced apart passages formed in said,nner casing, said passages being arranged in a gradually increasing pitch as they approach the bottom of said unit, a recess vformed in the upper end of said inner casingvcommunicating with said passages, and a recess formed in the lower end ofsaid inner cylindrical casing for receiving the refrigerant discharged from said passages.

l1. The combinationof a lrefrigerating unit adapted to be inserted in a closed circuit refrigerating system comprising a double walled cylinder having a spiral passage fornied between the Walls, the inner and outer walls of said passagebeing arranged so close that a maximum of conducting area is afforded b said walls in proportion to `the volume o said passage, means for, conducting refrigerant to said unit at one end of said passage andvmeans for conducting iso said refrigerant from said unit at the other FRENCHl E. DENNIsoN.` 

